Conventionally, in the field of technology related to an electrical characteristics test on a test object, such as a semiconductor integrated circuit, there is a known technology related to a connection terminal unit, which includes a plurality of connection terminals arranged according to a semiconductor integrated circuit and which has a function of ensuring electrical continuity by bringing the connection terminals into physical contact with the semiconductor integrated circuit. Such a connection terminal has a structure that includes at least a plurality of connection terminals and a connection terminal holder for supporting the connection terminals.
Each of the connection terminals described above includes two conductive contact members arranged at both ends thereof, and the contact members are coupled with each other by a coupling unit having a concavo-convex shape and are biased in the longitudinal direction of the contact members by a coil spring. Each of the connection terminals is extendable and retractable by the coil spring so as to come in contact with the semiconductor integrated circuit and can reduce a shock caused by a contact between each of the contact members and the semiconductor integrated circuit. The force applied to the semiconductor integrated circuit by the coil spring enables the contact members to assuredly come into contact with the semiconductor integrated circuit.
As the connection terminals described above, for example, there is disclosed a connection terminal that can increase the length of an electrical connection portion without reducing the volume of a spring (see, for example, Patent Literature 1). Furthermore, a connection terminal of a low profile type is disclosed (see, for example, Patent Literature 2).